Self-contained service pump assembly



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July 10. .1962 w. Y. BROWN sELF-coNTAINED SERVICE PUMP AssEMBLY 4 sheets-sheet 3 Filed Aug. 4, 1960 Om vw Nm mm.

INVENTOR: WILL/AM lf 620m m sam.

AT'TORNEY W. Y. BROWN SELF-CONTAINED SERVICE PUMP ASSEMBLY July 10, 1962 4 Sheets-Sheet 4 Filed Aug. 4, 1960 N m w w m m Y. w, M m. M S U. L 5 s- .H ML W. a O om. o mm. w r||| 1 en: I-- WS .55.2 vi m2 QN-m. .MN

A'ITORNEY il'nited States p v I 3,043,224- kSELF-CN'I'AINED SERVICE PUMP ASSEMBLY WilliamV YrBrown, Chariotte, N.C., assignor to Brown Grease Gun Company, Inc., Charlotte, N.C., a QQI'Poration of North Carolina 4 Filed Ang. 4,-1960, Ser. No. 46,633

^' 2 Claims; '(Ci."103-'23) Thisinvention relates to a service pump assembly and more particularly to lubricating and dspensing 'apparatus which comprises a battery of -dispensing units-selectively driven from a vcommon source -of power and designed to service various types of mechanical equipment.

In servicingjheavyduty motor and lfactory equipment, for example,'it becomes-necessary to dispense large quantities of greases, gear oils, hydraulic-oils, fuel voilS,-gasoline, compressed air, -and the like. -These substances are usually dispensed intermittently -and--at relatively high pressures, thus necessitating frequentstartng and stopping which results in -high load filuctuation.y The load fiuctuationvaries -notonlyineach separate dispensing unit, -.but also with the number of units inoperation at a particular time: '-As-a result of -the high load fluctuation, it fhas been found desirable to employ a continuously Operating power -source -fromwhich eachseparate -unit can lie-drivenVas-desired.V -In my -PatentyNo.--2,00S,850,-dated- July 23-1935, there is disclosed -a lubrication Vapparatus-comprising a plurality-V of selectively -operated reciprocable pumps :driven from the -same continuously operatingpower source,-andin Which-each-of the pumpv pistons is con- -nectable to the power source-by a latch mechanism.-- Although-such apparatushas proven satisfactory in -some types of dispensing operations,- it dos not provide Optimum advantages in heavy duty operations. A- number of adverse factors have-been encountered when making suchuse from this prior device, vsuch as Lthe-Shock produced upon latching, the vinstability of-the-latched-connection, and-the difliculty ofymaintaining alinement of thepiston and -itsreciprocating means when |the -parts -are unlatchedv f It its-therefore an object of this -inventionV toprovide a battery of lubricating and dispensing units, each'of which 'is conuectable to a Vcontinuously Operating-power source 'by an-v improved mechanismwhichwill -overcomethe above-mentiOned'difiicul-tiesf Specifically, I have-provided 'an electro-magnetically- -oprated-friction-clutch, Which clutch cooperates-with both the -power sourceV a-nd the dispensing unit in a novel manner to provide the requiste .flexibility and dependability of operation- It is another object-of'this invention--to -provide a double-acting lubrication-pump operated by a continuously Operating power source, in combination withanovel type of pressure controlled electromagnetic -friction clutch, operatively Vcon'necting the power source With the I-t is a further object ofV this inventionto provide a pressure controlled-reciprocatory lubrication-pump hav- -inga self-Cleaning check 'valve arrangement disposed in the pump-Outlet con-duit. -This -valvearrangement'com- 4prises a pair of spaced spring-pressed balls connected in series in the pump Outlet in such a manner as to prevent 'reverse flOw of the lubricant. When' foreign matter in the lubricant becomesfllodged in one of the vvalves of an arrangement, the other .valve will function normally while the intermittent flow of the lubricant tends to dislodge the matter. In the present embodiment, such a valve arrangement is located inl each of theV two :out-lets of the double acting pump assembly; p

It is another object of this invention to provide a pressure controlled reciprocatory'ipump having its'piston t C 3,043,224 gg Platenied July 10, 1962 reciprocated by a cam operated Scotch yoke, in combination With mens *tot wmafi lly, elnllg the yoke With/the'pistss'i i* 'inrdcatsflyii-eefiflg It isfyet'anothery object of'thi'sinvention to provide a self-.contained'service pump assembly having seleetively operable units, each capable of performing ya different servicing-operationf- V4lt is still another-.objectof this=invention to provide a self-contained service' pump assembly'of thegclass described, Which is suificientlylight and: compactto render it-portable'; The/ ,presentrinvention is especially useful when it is desired -to-service equipment at its Operating site, *or at'the point ofibreak down in 'case 'of automotive equipment. The facilities of a modern service 3station canthus be Vmadeavailable-without 'moving the^-equip-d ment to be servicei- -1 jl Itis another object of this inventiOn--to provide the combination Vof Va- 'lubricationpump,, 'an electro-magnetic clutch for-driving the same, ^andselectively operable means -responsive-to different pressures at the pump -outletforactua-tingjtheclutch. ---Some Ofthe :objects of the=- invention -having -been -stated,^ -other objects -will appearas-the description proceeds when taken in connection 'with the acompanying drawingsin-whichfg- -1 FIGURE--l is-an elevational-view showinga-battery of pressure control-led service pump units driven-from a common source-of power;- V-FIGUREfZ is aV sectional -plan viewr taken along line 2-2 inFIGURE 1-;'-v

q -v--F-IGURE-; is -an*elongated vertioalsectional view through a double--acting grease pump taken along line 3"-3 in FIGURE 2; g w h -FIGURE;-4 is an enlarged transverse sectional -view through -the-.grease -pumpingassembly; andytakenalong line 4-4 in FIGURE l; g FI'GURE --5-T isf-an enlarged-l transverse-sectional view through -the--gear oil pumping unit, and taken along lines S s-ini-*IGURi-:s1-=andv.:;V ff: FIGUREV 6 -is a= transverse'sectional detail view through the -electro-magnetic clutch,- *and 'taken along line'n-G in FIGURE-t;4 w;

FIGU-RE 7- is a-transverse sectional detail view through the electromagnetic clutch, 'and taken ralong'line 7 "-\7 in F1GUR-E4; v W' -FI'GURE -8 -is a-transverse-sectionalldetail viewthrough the electromagnetic clutch, .and-taken 'along- -l ine, 8- '8 in 'FIG-URE 4121101 j i,f;;.': i

FIGURE 9\i s a schematic wir-ing diagram of the'iuven- FIGURE- -170- -is a -view of afselectively voperable presassembly, and

v sure-actuatedyswitch.adapted -to Icontrol the operation of the -lubrica-tngapparatus Referring more particularly -to the drawingstheflnumeral 10 denotesa-base member upon which-is mounted a power unit .-s=uch-as- -gasolineengine 1'1; A' housing 12 is also mounted upon base 10, which-housing supports grease= pump assembly-13.- Located at spaced'points longitudinallylof basev 10 are -gear oilpump ^-unit- 14, hydraulic Ioil -pump unit 1 5, air--eompres'sor-unit-l, and gasoh'ne-Or-fuel oilpumpingnnit-Hw- -l f 4 i. VEngine 11,has a--V-t-ypedrivepulley -20 upon vwhifeh is rnounted V-belt 21,L said -belt being also mounted on anothen'V-typ'e pulley 22 :of *eleotro:magnet-ic-lclutchV broadly designated by reference character 23 (FIGURES-.=1, 2

and 4),. The huboffpulleyllis mounted-i-upon-the outer- .race Of. ball hearing. 26., the-inaeIj-.race-ot said-hearing The disk h milt 'fvt-5.:; 1 to. anti' ub 27 securly fit-s around bushing 29, said stud ibolts 65a.

-by any suitable means such as key 31. The inside face of pulley 22 (FIGURE 6) has the inner ends of leaf Springs 33 secured thereto las Vat points 34. 'The outer ends of each of said lSprings is hent axially away from theI inside face of pulley 22 and is secured as at 35 to annular conductive friction ring 38. -One face of ring 38 is ydisposed opposite to and engageable with a fn'ction lining 39 secured upon oney face of the frict-on disk 28. When the clutch is in' disengaged position as shown in 'FIGURE 4, a small clearance 40 separates lining 39 from friction ring 38. Thus, the leaf Springs 33 yieldably support vfriction ring 38 for movement axiallly of shaft 30 and toward and away from lining 39.

By inclim'ng the ileaf Springs 33 to a non-radial position relativeto the axis of rotation, a slightV relative rotation occurs between friction elements 68 and 39 immediately uponV-engagement, thereby producing a gradual transmission of power and eliminating damage to the pumping mechanism rcsulting from impact and Shock.

- VThe'face of friction disk 28 remote from lini-ng 39, has

k an aunular recess 44 therein. A stationary ring 45, made of conductive material such as magnetic steel, is adapted to fit into recess 44 so that -a s-light clearance 46 Will existV between the proximate surfaces of the respective members.

Ring is supported hy plate 47 which, in tum, is secured to al-uminum hulb 48 as at 49. The flange of hub 48 is Secured as at 50 to housing 12.

Ring 45 has a coil 53 therein, one end of said coil being connected as at 54--to lead Wire 55, and the other end of the coil being connected to ground Wire 56 as at 57. Wire 56 is grounded upon steel bolt 50 (FIGURE 4).

When the coil '53 is de-energized, the pulley 22 rotates idly about hub V27, bushing 29 and Vshaft 30, the three lastnaaned members remaining stationary. When, however, current flows through coil 53 from VWire 55, an electromagnetic field is created which causes one face of rotating friction ring-38 to move axially into engagement With lining 39 of friction disk 38, thereby causing members 22, 28, 30, 38 and 39 to rotate in unison.

' Secured' in hub 48 is a pair of alined ball bearings60 bers 86 ofy the respective housings are connected byV a by-pass conduit 88.

A pump cylinder 91 penetrates each of the housings 83 and 84, as well 'as the housing Chambers 86. Each cylinder 91 is provided With an enlarged head 92 fittingagainst one outer Wall of the cylinder, and a nut 93- threadalbly secured on :the other end of the cylinder and fitting against the other outer wall of the housing, thus securing the cylin. der in position. i

The cylinders 91 have Ialined longitudinal bores 94 therein, respectively, and each of these bores communicate With a chamber 86 by means of a plurality of radially disposed boresV in the cylinder. v

The alined cylinder bores 94 areralso alined with the Scotch yoke 77, and the proximate ends of the bores have the ends of pistons 96 mounted therein, the other ends of said pistons being attached to the opposite sides of yoke cover 65. Cover is Secured to casing 61 by means of Casing 61V has flanges .66 in which slots 67 are provided. A bolt 68 penetrates each of the slots 67 and is threadably lSecured in housing 12, thereby permitting longitudinal adjustment of the position of the pump assembly 13 (FIGURES 1 and 4). p

Shaft 64 has fix'edly'mounted thereon adjacent the gear 63 an eccentric 75, Which eccentric is -conrfined between verti-parallel surfaces 76 Vof Scotch Vyoke 77. ByV observing FIGURI 4, it can be seen Vthat one side of yoke 77 engageshosses 78 on cover 65 while itsother side engages the proximate face of gear 63, thereby restricting the lateral movement ofthe yoke as it is reciprocated horizontally lby eccentn'c'75.

The HScotch'yoke 77 is adapted to operateV -a pair of i reciprocatory pump units 1broadly designated by reference characters-81 and 82,.located at opposite ends of the pump casingV 61 and alined with the Scotch yoke. These pump units are vopposite hand one to another except for details Whichy Will be described later; consequently, like Vreferencecharacters will be .applied to like parts of the respective units. i

'IPump units 81'and 82 comprise housings 83 and V84 re- 'i spectively, said housings being securedlto they opposite ends of casing-61 by means of stud lbolts 85. Each of the I housings 83 *and 84-'ha-s -a hollow chamiber 86 therein and 77 in a manner which will be later described.

It will be observed from FIGURE 3 that the overall length of yoke 77 and attached pistons 96 is substantially the same asv the distance between the radial borcs 95. Hence, as the yoke and pistons are reciprocated, the piston of one of the pump units will draw a charge of grease from its associated chamber 86 through bores and into longitudinal bore 94, While |the piston of the other pump unit expels a charge of grease from its associated bore 94.

in order to 'prevent binding and'to promote smooth operation of the'pump elements, the Scotch yoke 77 is attached to the ends of pistons 96 in such a manner that the yoke will'automatioally aline itself with'the pistons in response to the Operating stresses. This self-alining feature is made possible 1by providing a col'lar.v 99 on the proximate ends of each of the pistons, said collar fitting into a vertical slot 100 in yoke 77. A horizontally disi posed slot 101 intersects each of the Vvertical slotsV 100 at approximately the mid-point thereof, said horizontal slot being adapted to receive the end of piston 96 (FIGURES 3 and 4). The Width of slot 100 is substantially the same as the width of collar 99, but the depth of the slot is somewhat greater than the collar'diameter. Also, the heigh-t .ofrhorizont-al slot 101 is greater than the diameter of piston 96. Therefore, relative transverse movement between the ends of pistons 96 will be permitted by the abovedescribed clearances in response to the Operating stresses to cause the yoke to aline itself correctly with the reciprocating pistons. k Communicating With the outlet'end .of each cylinder bore 94 is a self-Cleaning check valve assembly broadly designated by the reference character 103. Briefly stated,

Vthis assembly comprises a pair of serially arranged check at the junction of the two bores. A lhall 108 is yieldably pressed against seat 107 by means of'compression4 spring 109 confined in bore 106 by means of nut V110.

. A vertically disposed bore 114' extends upwardly from al point in horizontally disposed bore 106 near Vthe valve seat 107, the upper end of said bore 114 extending to the surface of block104 and being closed by nut 115. Communicating with the upperportionfof bore 114 .is a second horizontally disposed bore 116 which, in tum, communicates With a larger alined horizontal bore'117. A'valve seat 118 is provided at the junctionof bores 116 and 117, said seat having a ball 119 yieldably held thereon by means of a compression spring 120. ISpring 120 is confined in bore 117 by means of nut V121.

smita-224 :w Each-ofthe serially arranged -checlcvalves serves to prevent reverse floW-ofgreaserinto the pump, vand in addition, automatically serves .as a spare when the companion valve becomes -clogged With foreign matter. Usua1ly1any obstructing matter willwbecome dislodged in a short::time,-due to the'reciprocatory, movement of the grease; columnin which the -obstructed :valve is located. Without this dual valve .arrangemenn the obstruction of a. valvewould interruptthe greasingoperation until the obstructing matter is removed. i i' The lower ends of conduits 124 and 125 are respectively connected to horizontal bores 120 of valve assemblies 103, there being one such assembly connected to the Outlet of each pump unit 81'and 82. Conduits 124V and 125 merge into pipe 126 (FIGURES and 3), said pipe 126 being connected to dispensing hose 127 Woundfuponreel 128. The outer end of hose 127 has a suitable dspensing nozzleI 129 Secured' thereon.V Grease issupplied to pumping units 81V and 82 through a common inlet conduit 131 (FIGURES 1 and 2), saidv conduit leading from the lower portion of grease container 132 mounted upon housing 12.

V The operation of grease pump assembly 13 is controlled bythe pressure in its delivery hose 127, vwhich pressure is adapted to operate either the high-pressure switch 134 or the low-pressure switch 13411 depending upon the position o f 4selectively operable control switch 155a. In the presentinstallation, the switch 134 permits pump operation under pressures ranging from 1,000

lbs./sq. in. to 12,000 lbs./sq. in., and switch 134a under pressures ranging from 100 lbs./sq. in. to 1,000 lbs./sq. in. The ranges mayV be varied, however, by means' of .an adjustment mechanism comprising a portion of each switch and more fully described in Patent No. 2,1l1,969. When, for example, a predetermined high pressure of 12,000 lbs. per square inch has been built up in the hose, the high-pressure switch 134 is automatically opened (FIG- URES 9 and to sever the flow of current to electromagnetic clutch 23, vthereby disconnecting the grease pump assembly from its continuously* Operating source of power; and when a predetermined low pressure of 1,000 lbs./sq. in. is reached in hose 127, the switch 134 is automatically closed to establish a flow of current through clutch 23 and to connect pump assembly 13 with its power source. Likewise, When the low-pressure 13411 has been selected for operation, the flow of current through electro-magnetic clutch 23 will be interrupted at a high pressure of 1,000 lbs./sq. in. and reestablished at a low pressure of 10 lbs./sq. in.

Pressure switches 134 and 134a are connected to outlet conduit 126 by means of pipes 135 and are preferably of the type disclosed in the Patent No. 2,11l,969, dated March 22, 1938. Switches 134 and 134a are substantially identical except for the different sizes of the respective hollow cylinders in which reciprocate pistons 136 and 136a.

One end of a transversely disposed arm 138 is secured to the intermediate portion of each piston 136 and 136m, the other end of each of said arm fitting around insulation collar 139 on conductive rod 140. Rod 140, in turn, is slidably mounted in insulation cylinder 141, and the end of rod 14-0 has an enlarged contact head 14011 adapted to move relative to contact 14011 to make or break the electrical circuit flowing through the wires 55, either to switch 134 or 13441; and then from the selected latter switch the current flows to wire 143 and to coil 53 of electro-magnetic clutch 23. Spring 144 normally tcnds to urge the conductor 140, 140a in an opposite direction from cylinder 141 (FIGURE 10), Whereas spring 146 normally resists the pressure in cylinder 137. As the pressure in cylinder 1'37 increases, the piston 136 or 1361: will move to the left in FIGURE 10, and at the same time the members 138, 140 and 14011 Will be moved therewith to break the circuit.

lto

v; lt will tbe observed=1that member 141=1is mounted Ion ya bracket 141a, which bracket is threadably secured upon an adjustment rod 145, said.rod:having'knurled nut a on the-.end thereof wherebyr the rod fmay'be: manually turned to adjust thev gap bet'weerr Contacts-'141m and :140b and' thus establish a diiferentrange of operatingfpressures. The pressure'rangesassigned tol the-*switches 134= and 1 34a vshoul'dricomplement one another ibut-.notioverlap so that'both switches Will -not be operated fsimultan'eously. f Thefcurrent supplied to .clutchl 231is'derived from' storagebattcry 150, saidbattery *havingrone of its -terminals grounded at-151Liand its other terminal connected to a wire conduit 152. Ammeter 153 and-:master switch 154 are installed in conduit 152. Pull switch 155 is-installed in 'lead'wires- 551 of each ofith'e units 14 through 17, and the previously mentioned selectively-'operable pulll'switch 155a is installed -in the lead wires'55 of the lubrication unit 13. -Tosupply-fthe coil 53 of=theelectromagnetic clutch 2-3 With current, the master switch 154 and-one of the switches 155 and 155a-'areclosed; and When the pressure in delivery-hose V127 reaches a predetermined low, thepressure 'switch 134l or 13-4a will be operated to complete the circuit and 'reestablish pump operationl (FIG- URES9and10)'-- l f VBattery 150 is-ch'arged Vby generator 156 connected to battery poles by Wires 157'and 158. Starter'1'60 istconnected'to gasoline engine 11 -and to battery -150'in a conventional 'manner byfwires-161,- 162, 163*'and^7152. 'A- solenoid switch 164 is installed between -wires 161 and 162, whereas-a push-button switch 165 is installed between Wires'162and 163.-- iByclosing master switch 154 -andthen'the switch165-the engine F11- maylbe-started. Wire 166 leads from the magneto of engine 11 to ground 167, said Wire having switch 168 installed therein. Thus, the engine may be stopped by closing switch 168.

The continuously Operating engine 11 also drives four other electromagnetic clutches 23 respectively connected to the pumps of gear oil unit 14, hydraulic oil unit 15, compressed air unit 16, and fuel oil unit 17. These four clutches are connected in series with one another and with engine 11 by means of belts 170, 171, 172 and 173. Belt is mounted upon take-off pulley 174 of engine 11 and transmits the power to the four clutches 23 through the above-described interconnecting belts.

The four llast-named electro-magnetic clutches are identical in all essential respects to the clutch -23 described in detail in connection With the grease pumping assembly 13. 'Each of the shafts 30 of the latter four clutches, however, has a small pinion 30b formed on -its projecting end rather than the larger pinion 62 in the first instance. Pinions 30b mesh with larger gears 175 on shafts 176 of units 14, 15, 16 and 17 respectively.

Each of the shafts 176 of units 14, 15, and 17 drves a gear pump 178, said pump having an intake conduit 179 leading to one side thereof and an outlet conduit 180 leading from its other side. These outlet conduits each have a check valve mounted therein for preventing reverse flow of the rlulrn'icat-ing [materials or fuels.

By observ-ing FIGURE l, it Will be seen that the outlet conduit 180 of each of the pumping units 14 and 15 is connected to a pipe 183, said pipe being connected to a dispensing hose leading therefrom. Each hose 185 has a suitable nozzle 186 Secured on its outer end.

The operation of the air Compressor pumpng unit 16 is similar to Ithat described in connection with grease pumpingassembly 13, and accordingly is provided With a suitable conventional time interval switch 234. The opcration of pumping units 14, 15 and 17 is automatically controlled by the pressures in the respective delivery conduits and in a manner slightly different from that described in connection With unit 13. Units 14, 15 and 17 are each provided with 'flip switch 196 schematically illustrated in |FIGURE 9, which switch operates in- 7 stantly upon lowering of the pressure in the delivery hose.

Switch 1976 comprises a piston 197 having a conductve switch bar 198 connected thereto and adapted to close and open a gap in conduit 55 to control the -flow of current to electro-magnetic clutch 23. Bar 198 is held open by the pressure in the outlet pipe and moved to closed position by spring 199 when the pressure falls.

In the drawings and speci-fication, preferred em-bodiments of the invention are shown, and although specific terms are employed they are not intended for purposes of limitation, the scope of the invention being set forth in the following claims. V

1. Luhrication apparatus comprising a pump having a shaft by -whch it is driven, a prime mover for driving said shaft, rotary means loosely ymounted on said shaft, driving -meansV interconnecting said prime -mover With -said loosely mounted rotary means to Vcause the latter to be -continuously rotated, a st-ationary -magnetic ring member concentric with 'the pump shaft, a coil embedded in said ring member, africt-ion disk Secured upon said rotary means and axially movable of the shaft,

said disk being disposed within the field of magnetic flux of said Vring member, a second friction disk fixed upon said shaft and disposed between said first 'disk and said stationary magnetic ring, whereby When said coil is energized the rotation of said first disk Will cut the lines of magnetic flux produced by the ring member to cause the -first friction disk to be moved axially of the shaft and into engagement with the second friction disk, electric circuitV -means of said coil including a source of electrical current,

a plurality of pressure switches for controlling respectively a plurality of, ranges of pressures, means for communicating the pressures at the outlet of said pump to each of said pressure switches, an electrical Circuit for each said pressure switch, and switch means for selectively connecting said circuits with said current source.

2. Lubr-cation as defined in claim 1 -wheroin torsion spring means is provided for securing said iirst-na-med friction disk upon said rotary means whereby the Shock occurring from a sudden increase 'of 'torque will be damped.

References Cited in the file of this patent UNITED STATES PATEN'TS 773,523 Richards Oct. 25, 1904 8621,-673 Richards May 29, '6 828,326 Mian'zell Aug. 14, 1906 887,252 Jackson May 12, 1908 V 1,(}12,821 Cutler DecfZ,V 1911 V1,432,0-41 Scott Oct. 17, 1922 1,724,156 Winton Aug. 13, 1929,. 2,06%,392 VAcker Jan. 19, 1937f 2,160,97s Mot-.k June 6, 1939' 2,263,429 Sheen Nov. 18, 1941 2,415,265 Taylor Feb. V4, 1947 2,556,00i4 Sachse June 5, 1951 2,,561,7S6 Davis July 24, 1951 2,57-1,762 Rich Oct. 16, 1951 2,795,1911 Seter June 11, 1957 i FOREIGN PATENTS 253,153 vGreat Britain Oct. 28, 1926 

